The invention refers to positioning an object.
U.S. Pat. No. 5,561,564 describes a lens drive, and JP-A-01096612 shows a holding device for anamorphous optical elements. From DE-A-1943284, a device for adjusting optical components is known.
It is an object of the present invention to enable suitable position adjustment of an object. This problem will be solved by the features of the independent claims. Advantageous embodiments are shown in the dependent claims.
Positioning of an object is necessary, for example, when assembling optical components, such as a laser module. In such systems, individual light-conducting components must be aligned or positioned relative to each other with high precision. To do so, certain components, in particular components with a cylindrical body, must be positioned by rotating to achieve the intended orientation. Optical components that must be positioned in this manner are, for example, lenses, prisms or filters, more particularly polarization filters. To achieve this, these components are held in a holder that can be positioned by rotation in the described manner.
In order to perform the rotational positioning of the respective object or the respective holder with respect to their longitudinal axis, a high effort with respect to the necessary equipment is necessary if there are very high requirements for the accuracy of the position adjustment. For the precise alignment of an optical lens in a laser module, for example, it may be necessary to position the lens holder with an accuracy of less than 1 xcexcm. The accuracy of the achievable positioning can depend, among other factors, on the net mass of the components used for positioning and holding the object and on their elasticity.
The invention is based on the idea to provide a rotation device for the rotational adjustment of an object held by a holder where the rotation device makes possible the rotational adjustment of the held object with respect to the holder. In the positioning device according to the invention, the object is therefore rotated within a holding cup of the holder while the holder, and a holding arm that may be connected to it, remain stationary. This methods makes possible an extremely light construction for the rotation device because rather than turning the holder with the held object, or the holding arm with the holder and the held object, only the relatively small, and thus relatively light, object has to be rotated. With the achieved reduction in weight, the holder with the rotation device or the complete holding arm can be designed much lighter, thus reducing imprecision due to the net mass and the elasticity.
On the object to be positioned, there is a drive component in form of at least one radial ledge and/or at least one radial recess and the rotation device or positioning device engages with this drive component when making rotational adjustments of the object.
According to another embodiment, the rotation device can have a rotational drive located on the holder, which contains a first drive component, wherein the object to be positioned contains a second drive component, which is designed complementary to the first drive component and which reaches into the first drive component when the object is inserted into the holding cup.
In the above-mentioned embodiments, the rotation device thus acts directly together with the object to be positioned so that a component of the rotation device, i.e. the respective drive component, is formed directly on the object. This considerably reduces the equipment requirements on the holder, in particular reducing the weight. By creating the respective drive component on the object, an additional function is thus integrated in the object to be positioned.
The holding cup also has a double function because the object to be positioned rotates inside the holding cup during the adjustment so that the cup serves as a pivot bearing for the object.
In a first development, the first drive component can be created by a pin that extends parallel and eccentric to a rotational axis which is perpendicular to the longitudinal axis of the holding cup, wherein the first drive component with the rotational drive rotates around this rotational axis while the second drive component is created by a recess on the outer cover of the object into which the pin reaches. By rotating the pin around the mentioned rotational axis, it pulls along the object with the recess, driving it in direction of the circumference and causing the object to rotate around its longitudinal axis in the holding cup. This development can be realized especially economically.
In a second development, the first drive component can be created by a first conical gear wheel, the rotational axis of which is perpendicular to the longitudinal axis of the holding cup, wherein the second drive component is created by a second conical gear wheel, which is created on the object and which engages with the first conical gear wheel when the object is inserted in the holding cup and the rotational axis of which is concentric to the longitudinal axis of the object. While the drive using the pin and recess described above is relatively limited with respect to the possible angle range, such a gear wheel drive can be set to essentially any angular displacement. However, the design of the gear wheels is relatively expensive for relatively small components.
In a third development, the first drive component can be created by a first radial gear wheel, the rotational axis of which is perpendicular to the longitudinal axis of the holding cup, wherein the second drive component is created by a second radial gear wheel, which is created on the object and which engages with the first radial gear wheel when the object is inserted in the holding cup and the rotational axis of which is concentric to the longitudinal axis of the object. In this development, unlike in the previously described variation, the first gear wheel can be relatively large provided that there is sufficient space in radial direction on the holder.